Method of retarding the setting time of cement



Osaku Matsuda and Norihiro Kudo, Tokyo, Japan, assignors to Onoda Cement Company, Limited, Yamaguchi Prefecture, Japan No Drawing. Filed Jan. 6, 1964, Ser. No. 336,072

3 Claims. (Cl. 106-90) This invention relates to a method of retarding the setting time of cement selected from Portland cement and a cement mixture comprising Portland cement by adding a retarding agent consisting of at least one silicofluoric compound and at least one organic surface active agent, together with and without an additional component selected from inorganic acids and organic acids.

An object of this invention is to provide a method of retarding the setting time of Portland cement in order to give an easily controllable softness and a workability to Portland cement paste, mortar and concrete especially at elevated temperatures in summertime as well as to give an improved development of strength to them.

Another object of this invention is to provide a method of retarding the setting time of Portland type cement comprising blast furnace slag, siliceous material or pozzolanic material in order to give an easily controllable softness and a workability to Portland type cement paste, mortar and concrete especially at elevated temperatures in summertime as well as to give an improved mechanical strength to them.

It is well known that starch, cellulose, sugar, phosphoric acid, organic acids, salts of organic acids and silicofluorides have the retarding effect on the setting time of cement. However, such retarding agents are not practically usable, because when such agents are used as the retarding agents the slightest variation in their amounts, the mixing procedure or the mixing temperature seriously retards the setting time of cement or impedes the development of the strength or causes the cement to set undesirably too fat-in any way because the action of such agents for the cement is too unstable and therefore they are precarious in practical use.

In order to achieve the foregoing objects and overcome the defects adherent to the prior retarding agents, the inventors have long investigated and have found a new and elfective retarding agent for cement.

This invention relates to a method of retarding the setting time of cement selected from Portland cement and a cement mixture comprising Portland cement by adding a new and effective retarding agent consisting of at least one silicofluoric compound as the first component and at least one or amgggfgce gctiggagent as the second component together with and without an additional member selected from inorganic acids and organic acids as the third component.

In accordance with this invention, silicofi compounds used as the first component inducer water insoluble or water slightly soluble silicofluoric compounds such as sodium silicofluoride (Na siF potassium silicofluoride (K SiF barium silicofluoride, (BaSiF and calcium silicofluoride (CaSiF or water soluble silicotfth". Fri 1 Nit ii 3,317,327 Cg Patented May 2, 1967 w used as the second component as a lipophilic radical and a hydrophilic radical in its molecule and it includes W5 and non-ionic nts. E'typrcal examples of'fie anient are calcium, sodium, potassium or ammonium salt of lignin e sodium, ammo- 65in" att alcohol having carbon atom an r; 0 mm or potassium salt'of alkyl aryl sulfonic at having carbon atoms of 8 to is'mn'filryrsmsatnm or potassium salt of condensation product of naphthalenesulfonicacid and fogmaldehyde. The typical examples of the non-ionic surface active agent are addition compounds of ethylene oxide and alkyl ether, alkyl phenol ether, alkyl ester, alkylami alkylamide or sorbit-an alkyl ester having carbon atoms of 8 to 18 in the alkyl.

It should be noted that such surface active agents may contain a builder such as sodium sulfate, sodium carbonate or carboxy methyl cellulose.

In accordance with this invention, the inorganic acids and the organic acids used as the third component in acetic acid and succinic acid and a mixture thereof.

The retarding agent comprising, the silicofluoride and the. organic surface active agent or the silicofluoride, the organic surface active agent and at least one acid selected from the inorganic acids and organic acids has a remarkably distinguished effect for retarding the setting time of cement, developing the strength of cement and obtaining highly stable and homogeneous cement paste, cement mortar and concrete.

The retarding agent in accordance with this invention has a surprisingly distinguished effect for retarding the setting time of cement as compared with the case of using the silicofluoride alone and also has an excellent effect for developing the strength of cement, for obtaining a highly homogeneous cement paste, cement mortar and concrete, thereby giving a greater workability to them and decreases an amount of mixing water to cement as compared with the case of using the silicofluoric compound alone. In addition, the amount of the silicofluoric compound can be reduced when it is used together with the organic surface active agent.

In order to explain the mutual actions and elfects resulted from the use of silicofluoric compound and an organic surface active agent in combination, the setting tests for Portland cement containing the silicofluoric compound or the surface active agent or both of them were conducted in the method defined under the Japanese Industrial Standards, 118 -R 5201 (1959) and the datum resulted from the tests are shown in Tables 1 to 3. Tables 1 and 2 show the results of the comparative examples and Table 3 shows the results of example of this invention. in tables the percentages given are by weight and the figures in the parentheses represent the index numbers of the cement containing a silicofluoride or a surface active agent or both of them against the index number of the cement without them which are calculated as 100.

As obvious from Table 2, only lignin sulfonate displays its retarding effect but other surface active do not display their retarding effects.

agents Ratio of Ratio of Setting Time Kinds of silicofiuoric Kinds of Surface Active Test silicofiuoric Compound Surface Active Agent to Nos. Compounds to Cement Agent Cement Initial Setting Final Setting (Percent) (Percent) (Hour-Minute) (Hour-Minute) 2-21 (100) 35-35(100} 0.10 400(l71) 534(155) 0. 10 3-32050) 507(l43) 0. 10 4-36(l96) 555(165) 0. 10 0.006 4-5200?) 603(169) O. 10 0.003 4-02072) 5-24(l51) 0.10 0.006 4-3809?) 5-55(l65) 0.10 0.10 5-31 (235) 6-50(l9l) 0. 10 0. 20 6-51 (N2) 832(238) 0. 10 0. 10 435(195) 603(169) 0. l 0. 20 22(228) 659(195) 0. 0. l0 449(205) 559(167) 0. 10 0. 5l0(220) 6-3208?) 0.10 0.10 4-15(l81) 531(l54) 0.10 0.20 448(204) 6l0(172) Nora-A, is ammonium salt of sulfuric acid ester of higher fatty alcohol made of palm oil. A: is calcium salt oflignin slflf yet y e er.

TABLE l.VARIATION OF THE SETTING TIME OF PORT- LAND CEMENT CONTAINING SILICOFLUORIC COM- POUND ALONE Table 3 clearly shows the mutal effects resulted from the use of the silicofiuorides and the organic surface active agents in combination. As seen, for example, from test Ratio (silicofiuoric setting Time 3 No. 8 the combination of 0.1% of magnesium silico- Compound to Cement fluoride and 0.1% of calcium salt of hgmn sulfonic acid f shows a more higher retarding effect than the case of srlr g r P t Ifiitial fi eg i 1 2133; $5322 using a 0.2% lignin sulfonic acid alone as shown in test gf f f men No. of Table 2 or using a 0.2% of magnesium silicofluoride alone as shown in test No. 11 of Table l.

0 2-21 100 H5 0 In accordance with this invention, the water insoluble 3.85m 5:238: 3; 012? or water slightly soluble silicofiuoric compounds are 0113 $2 6 H7043) usually added to cement in an amount of from 0.01%

.2 528% to 0.5% because said silicofiuoric compounds decrease 100 2-51 121) H2031) their retarding effect when they are used in an amount .825 215383; of above 0.5% as single component respectively. And

1 13 alis), (the water soluble silicofiuoric compounds are usually 0.20 4- 7 a e to cement in an amount of from 0.01% to 1% 8 15-oo 4o0i However, it should be understood that such amounts of 2.00 900( the silicofiuorides are not critically defined ones as their effects are variable depending on the composition of As obvious from Table 1, the retarding effect of sodium Cement Paste, Cement mOrtar and Concrete, and also the silicofluoride (Na SiF which is water hard soluble is rapidly decreased when its amount reaches above about temperature for working of them.

In accordance with this invention, the ratio of the 0.5% but the retarding effect of magnesium silicofiuoride (MgSiF which is water soluble is increased as its amount is increased.

TABLE 2.VARIATION OF THE SETTING TIME OF PORT- LAND CEMENT CONTAINING ORGANIC SURFACE ACTIVE AGENTS ALONE Ratio of Organic Sur- 1 -21000 3-35000 o. 003 2-2o(99 51-36(100) 0. 006 241 97 3-35(100) 0.10 245017 3-4600 0. 20 s-ososm a-s4o09) n. 10 215(96) saw. 0. 2o 2-23 101) 336(100) Norm-A1 is ammonium sa lcoho -made of pni-m bi K m; i W

1 3 is polyoxyethylenenonyl phenol ether.

1t of sulfonic acid est r of higher fatt a 15 rn s" o ignin leaf-id.

silicofiuoric compound to the organic surface active agent is not critical as the organic surface active agent can be optionally selected and usually used in an amount of 0.001% to 0.5 by weight of cement depending on its dispersing property or air-entraining effect.

Further, in accordance with this invention, the inorganic acids or the organic acids can be usually used in a ratio by weight of said acids to the silicofiuorides being below 50%. However, it should be understood that the ratio must be optionally selected because the interval between the initial setting time and the final setting time of cement elongates with the ratio of said acids to said silicofiuoric compounds increases.

In order to explain the mutual actions and effects resulted from the use of magnesium silicofluoride, lignin sulfonate and an inorganic acid or an organic acid in combination, the setting tests for Portland cement were conducted in the method defined under the Japanese Industrial Standards, 118 R 5201 (1959) and the datum resulted from the tests are listed in the following Table 4.

A TAINING EITHER OR ALL OF THEM Amount 01 Setting Time Test Amount of Lig'nin- Amount 01 Nos. MgSiF Sulfonate Acid (percent) (percent)) (percent) Initial Setting Final Setting (Hour-Minute) (Hour-Minute) 0 0 2-21 (100) 3-35 (100) 0.10 0 0 4-00 (171) 5-34 (155) 0.10 0 Orthophos- 4-42 (200) 6-49 (186) 1816111110 acid 0.10 o. -l 16 6-11=263) 8-15 (230) 0 0.10 0 2-45 (117) 3-46 (105) 0. 10 0. 10 Btargi acid, 3-46 (160) 7-03 (197) 0.10 0 sr ginc acid, 4-53 208 1-10 200 0.10 0.10 "100 6-32 (278) 8-50 (247) 0. 10 0. 10 Agagilc acid, 4-12 (179) 6-47 (189) Further, in order to explain the mutual actions and 25 effects resulted from the use of magnesium silicofluoride and an organic surface active agent in combination, the

reaching 4000 p.s.i. The concrete used in this test was prepared by mixin 300 kilograms of Portland cement per cubic me er 0 concrete, 176 kilograms omer per cubic meter of concrete and sand in an amount of 41% by weight of the total aggregate. The datum resulted from the tests are given in the following Table 5.

TABLE 5.-TEST FOR THE SETTING TIME OF CONCRETE 'BYMEASURING THE PROCTOR.

NEEDLE PENETRATION RESISTANCE (P.S.I.)

Amounts 0! Kinds of Surface Amount of Sur- Initial Setting Final Setting Test Nos. MgSiFs Active Agent face Active (Hour-Minute) (Hour-Minute) (percent) Agent (percent) 0 0. 20 7-25 (139) 8-30 (129) 0.10 0.10 9-30 (178) 10-50 (165) 0.10 0. 20 12-25 (233) 14-25 (219) 0.20 0.10 11-30 (216) 12-45 (194) 0. 20 do 0. 20 15-25 (289) 17-35 (267) 0 Polyoxymethylene 0.10 5-10 (97) 6-20 (96) nonyl phenol ether. 0 ...do 0.20 5-25 (102) 6-30 (99) 0. 0.10 7-55 (148) 8-55 (135) 0. 0. 8-40 (163) 9-45 (148) 0. 0.10 10-35 (198) 1140 (177) 0. do 0. 20 11-55 (223) 13-00 (198) 0 Naphthalene sulfo- 0.10 5-05 6-00 nateiormaline condensation product. 0 .do 0.20 4-50 (91) 5-55 (90) 0.10 0.10 7-50 (147) 8-55 0.10 0. 20 8-20 (156) 9-35 (146) 0.20 0.10 10-00 (188) 11-10 0. 20 0.20 1100'(206) 12-15 (186) setting tests for Portland concrete were conducted at 20 C. in the method defined under American Standard for 55 Testing Materials (ASTM) C 403-61T. This test is a test for measuring the Proctor needle penetration resistance of concrete. In this test, the expected slump is 15 cm. and the initial setting time means the time for the (5 penetration resistance reaching 500 p.s.i. and the final setting time means the time for the penetration resistance The following Table 6 shows the compressive strength 0 cubic meter of concrete and sand in an amount of 38% by weight of the total aggregate of which the largest diameter is 25 mm., and its slump was 10 cm.

TABLE 6.THE SETTING TIME AND THE COMPRESSIVE STRENGTH OF THE CONCRETE Amount 01 Setting Time Compression Strength (kg.lcm.=)

Calcium Amount 01 Amount of Salt of Test Nos. MgSiFo H POr Lignin Initial Final (Percent) (Percent) Sulfonic Setting Setting 3 days 7 days 28 days Acid (Hour- (Hour- (Percent) Minute) Minute) i Y 4 n J 1.

l n h aasghp qaye ylenelndm p31 It is obvious from Table 6 that the retardation of the amount of from 0.001% to 0.5% by weight of said development of compressive strength of the concrete can cement. be avoided by applying this invention. 3-' A method of retarding -the setting time of cement What we claim is: selected from Portland cement and a cement mixture 1. A method of retarding the setting time of cement 5 comprising Portland cement, which comprises adding selected from Portland cement, and a cemenfmixtu're magnesium silicofiuoride (MgSiF in an amount of comprising Portland cement, which comprises adding sofrom about 0.01% to 1.0% by weight of said cement, 2L (Na siF in an amount of from a calcium salt of lignin sulfonic acid in an amount of abfifiimm to 0.5% by weight of said cement and at from 0.001% to 0.5% by weight of said cement, and at least onegor ganigwcgyugent selected from the least one acid selected from the group consisting of group consisting of an ammonium salt of the sulfuric orthophosphoric acid, boric acid, acetic acid and succinic acid ester of a higher fatty alcohol, a ca -salt of acid in an amount of below 50% by weight of said maghgmn acid, polyox e-non 1 her nesium silicofluoride. polyoxymethylene-o e "er, andnaphthalene sulfonate-formaldehyde condensation product in an References Cited by the Examiner amount of from 0.001% to 0.5% by weight of said UNITED STATES PATENTS cement. 1,644,964 10/1927 Welch 106-90 2. A method of retarding the setting time of cement 1,726,403 8/1929 Mathey l06315 selected from Portland cement and a cement mixture 2,006,426 7/1935 Weiler l0692 comprising Portland cement, which comprises adding 2,113,375 4/1938 Himsworth et a1 106-315 magnesium silicofluoride (MgSiF in an amount of from 2,211,368 8/ 1940 Dickens 106-315 about 0.01% to 1.0% by weight of said cement and at 2,575,599 11/1951 Silverman 106-90 least one organic surface-active agent selected from the 2,927,033 3/1960 Benedict et a1 106-90 group consisting of an ammonium salt of the sulfuric 3,053,673 9/1962 Walker 106-90 acid ester of a higher fatty alcohol, a calc'u TOBIAS E LEVOW, Primary Examiner- To lyoxyriiethylene-nonyl phenol ether and naphthalene HELEN MCCARTHY Examiner sulfonate-formaldehyde condensation product in an S. E. MOTT, Assistant Examiner. 

2. A METHOD OF RETARDING THE SETTING TIME OF CEMENT SELECTED FROM PORTLAND CEMENT AND A CEMENT MIXTURE COMPRISING PORTLAND CEMENT, WHICH COMPRISES ADDING MAGNESIUM SILICOFLUORIDE (MGSIF6), IN AN AMOUNT OF FROM ABOUT 0.01% TO 1.0% BY WEIGHT OF SAID CEMENT AND AT LEAST ONE ORGANIC SURFACE-ACTIVE AGENT SELECTED FROM THE GROUP CONSISTING OF AN AMMONIUM SALT OF THE SULFURIC ACID ESTER OF A HIGHER FATTY ALCOHOL, A CALCIUM SALT OF LIGNIN SULFONIC ACID, POLYOXYMETHYLENE-NONYL PHENOL ETHER, POLYOXYMETHYLENE-NONYL PHENOL ETHER AND NAPHTHALENE SULFONATE-FORALDEHYDE CONDENSATION PRODUCT IN AN AMOUNT OF FROM 0.001% TO 0.5% BY WEIGHT OF SAID CEMENT. 